Toxicity of methyl methacrylate in dentistry

Initially, denture teeth were made of ceramic material. With the advent of polymethyl methacrylate (PMMA) in the 1940s, a new material was introduced for the fabrication of denture teeth. Denture teeth are currently made of either methacrylate-based resins (acrylic resin) or ceramics. Loss of teeth, which may be due to trauma, dental diseases, pathology, or otherwise not only alters the psychological thought of the patients but also disturbs the esthetics, phonetics, and functional occlusion. Replacement of missing teeth is highly essential in order to restore the defect and regain function as best as possible.

The U.S. Environmental Protection Agency (EPA) explains that exposure to methyl methacrylate is typically occupational and that manufacturers of the compound and its polymers, along with dentists, dental technicians, nurses, and doctors are potential candidates for exposure. Methyl methacrylate (MMA), in liquid form, is used to restore the damaged areas of acrylic dentures to normal function and appearance, quickly and efficiently. A widely used monomer in dentistry and medicine has been reported to cause abnormalities or lesions in several organs. Experimental and clinical studies have documented that monomers may cause a wide range of adverse health effects such as irritation to skin, eyes, and mucous membranes, allergic dermatitis, stomatitis, asthma, neuropathy, disturbances of the central nervous system, liver toxicity, and fertility disturbances.

Methyl methacrylate is a monomer of acrylic resin widely used in a variety of medical, dental, and industrial applications. Many dentists and dental assistants either personally work with methyl methacrylate (also known as methacrylate monomer, methyl ester of methacrylic acid, methyl-2-methy-2-propenoate) while making splints and other dental prosthetics or are exposed to the smell and fumes of the compound because their colleagues are using it in the immediate area. The main toxic effects of MMA exposure appear to involve the cardiovascular system. When exposed to MMA in the work environment, staff have been reported to suffer from hypersensitivity, asthmatic reactions, local neurological symptoms, irritations and local dermatological reactions. The integrity of latex gloves may also be compromised following exposure to MMA during surgical procedures. At present, MMA is not thought to be carcinogenic to humans under normal conditions of use. Nevertheless, sound occupational hygiene practices should still be used to help reduce workplace exposure to MMA during orthopaedic and other medical procedures. Surgical staff should avoid direct contact with MMA mixtures wherever possible, and room ventilation and adequate airflow should also be optimized.

Ductless Containment Hoods have been an excellent solution for controlling methyl methacrylate fumes in dental and denture laboratories. Sentry Air offers several additional types of engineering safety controls that will effectively filter the odor if a ductless containment hood is not a viable option [Example: a portable fume extractor with flexible arm- Model # SS-300-PFS].

“I can’t tell you enough how wonderful it is making splints. I use to suffer headaches every time I smelled Methyl Methacrylate. When I did them the entire office smelled of it. Now that I have my hood never a headache and absolutely no smell in the office or lab area. Worth every penny!!!! It is of great comfort that I am also not exposing myself and office staff to a potential carcinogen. I highly recommend this product to all my friends that make Maxillary Anterior Guided Orthotics or any splints for that matter.” Sincerely, Paul M. Baraban D.D.S.

The Jamestown Family Dental Clinic located in Sequim, WA serves Jamestown Tribal citizens and employees as well as members of the local community. According to Bill Laubner, Facility Manager, the dental clinic denture molds were creating overwhelming fumes. The center purchased a Sentry Air’s 18″ Wide Ductless Fume Hood Model # SS-218-DCH, one of the most compact fume containment hoods on the market. This ductless hood is designed to protect both the operator’s respiratory zone and environment from hazardous fumes, vapors, or particulate generated from applications performed within the hood. Despite the small exterior footprint of this hood, the interior working space provides a comfortable and spacious environment for operators performing a variety of processes.

The small structure of this system makes it an ideal solution and addition to a lab or room that has limited space or requires only a small containment area. This light-weight system has also be en used in a variety of time sensitive field-testing applications that require transportable equipment. Other uses for this fume hood include chemical fume control, epoxy and solvent fume control, pharmaceutical compounding containment, soldering applications, dust removal, biological applications, and many more processes that require the removal of fumes and dust.